A US woman who shot and killed her husband and two adult children before taking her own life is thought to have committed the shocking crime as a result of being ostracised from the religion she was raised in.

A federal judge sentenced a former Arkansas judge Wednesday to five years in prison — a stiffer punishment than prosecutors recommended — after he admitted giving young male defendants lighter sentences in return for personal benefits that included sexual favours.

Every time I tell a mate I’m doing a story on cryptocurrency, they invariably ask me the same two questions: should they invest their own hard-earned money, and which cryptocurrency will get them a Lamborghini/yacht/island quickest?

In a 60 Minutes online exclusive, reporter Liz Hayes quizzed Australian Prime Minister Malcolm Turnbull on his relationship with the unpredictable Twitter aficionado and US president Donald Trump ahead of their meeting at the White House Friday.

Abbott asked to speak for Tassie activist

The wife of jailed Greenpeace activist Colin Russell has made an emotional plea to Prime Minister Tony Abbott to intervene and prevent her husband being imprisoned by Russian authorities for another three months.

A St Petersburg court will decide on Monday whether to continue the detention of the so-called Arctic 30 while they await trial on piracy and hooliganism charges.

Ahead of the ruling, Christine Russell travelled to Canberra with daughter Madeleine to plead for the prime minister's intervention, in what she said had been a "nightmare" lasting 62 days.

"I'm asking Prime Minister Abbott and (Foreign) Minister (Julie) Bishop to please speak directly at a diplomatic level with the Russian government and Russian authorities to end this injustice that's been going on for 62 days now," an emotional Mrs Russell told reporters in Canberra.

"I just get overwhelmed - the thought that he's not going to be in our lives possibly for another three months while they investigate ridiculous charges of piracy and hooliganism.

"This shouldn't be allowed to continue."

The 59-year-old Tasmanian was one of 30 Arctic Sunrise crew members to be arrested by Russian authorities in September after two activists tried to scale a state-owned oil platform in protest against drilling in the Arctic.